[0001] The invention relates to a process for multilayer coating, in particular repair coating
of substrates, wherein a filler layer curable by means of high energy radiation and
a top coat layer are applied. The process can be used in the field of automotive and
industrial coatings.
Description of Related Art
[0002] It is known to use coating compositions curable by means of UV (ultraviolet) radiation
in vehicle coating. Coating compositions based on free-radically polymerizable binders
are in particular used in such applications. These coating compositions generally
contain photoinitiators. Coating compositions curable by means of UV radiation are
described, for example, in
DE-A-198 18 735 and
US-A-5,932,282.
[0003] It is likewise known in the context of vehicle coating to produce the various layers
of a multilayer structure, such as, filler, base coat and/or clear coat layer, from
coating compositions curable by means of UV radiation.
[0004] US-A-4 668 529 accordingly describes a one-component filler coating composition for repair coating
that is curable by means of UV radiation. Only reactive diluents are used as the UV
curable components. These comprise tripropylene glycol triacrylate and trimethylpropane
triacrylate. The composition additionally contains a physically drying epoxy resin
based on a bisphenol A diglycidyl ether.
[0005] DE-A-197 57 082 describes a multilayer coating process, in which the filler coating composition used
comprises either solely binders curable by free-radical and/or cationic polymerization,
or binders curable by free-radical and/or cationic polymerization and further chemically
crosslinking binders. Curing proceeds by means of high energy radiation.
[0006] However, known filler coating compositions curable by means of high energy radiation
also exhibit, in addition to the undisputed advantageous properties of UV curable
systems, several disadvantages, in particular if they are to be formulated and used
as priming fillers. Priming fillers generally perform or combine the function of a
primer and a filler in a single coating composition and are applied directly onto
the substrate to be coated without application of a priming layer. However, UV curable
priming fillers still exhibit inadequate adhesion onto metal substrates, such as,
aluminium, steel and zinc. Moreover, edge marks may occur on overcoating with further
coating layers and the coating compositions exhibit deficiencies with regard to stability
and/or flow.
[0007] US 5,091,211 describes a coating method, wherein a vinyl resin layer is coated with a coating
composition comprising a radiation-curable acrylourethane, a photoinitiator, an unsaturated
addition-polymerizable monomer and a mono- or diester of phosphoric acid in an amount
sufficient to improve the adhesion of the coating composition to the vinyl resin layer.
There is made no reference to direct coating metal substrates.
[0008] This invention provides a process for coating substrates that makes it possible to
apply filler coating compositions curable by means of high energy radiation that yield
coatings with excellent adhesion to various metal substrates. While retaining good
processing characteristics, the filler coating compositions should exhibit a balanced
relationship between good stability and good flow. In addition, when the filler layers
are overcoated, no edge marks should occur.
Summary of the Invention
[0009] This invention is directed to a process for multilayer coating of substrates comprising
the steps:
- a) applying a filler layer of a filler coating composition to a metal substrate,
- b) curing the resultant filler layer by irradiation with high energy radiation and
- c) applying a top coat layer of a colored and/or special effect base coat coating
composition and a transparent clear coat coating composition or a pigmented one-layer
top coat coating composition to the cured filler layer and curing the top coat layer;
whereby the filler coating composition comprises
- A) at least one binder capable of free-radical polymerization having fewer than three
olefinic double bonds per molecule,
- B) at least one ester of alpha,beta-olefinically unsaturated monocarboxylic acids
capable of free-radical polymerization having one olefinic double bond per molecule,
wherein the at least one ester of alpha, beta-definically unsaturated monocarboxylic
acids is a (meth)acrylic acid ester with cycloaliphatic alcohols, and
- C) at least one compound having at least one phosphoric acid group.
Detailed Description of the Embodiments
[0010] Preferred filler coating compositions that are used are those comprising 10-80 wt.%,
particularly preferably comprising 15-60 wt.% of component A) and 20-90 wt.%, particularly
preferably comprising 40-85 wt.% of component B), wherein the weight percentages of
components A) and B) add up to 100 wt.%. The filler coating compositions preferably
contain 1-15 wt.%, particularly preferably, 2-10 wt.% of component C), relative to
the quantity of the entire coating composition.
[0011] The filler coating compositions contain binders curable by means of high energy radiation
as component A). Binders curable by means of high energy radiation that may be used
comprise any conventional binders radiation-curable by free-radical polymerization
or mixtures thereof which meet the requirement of low functionality. The free-radically
polymerizable binders must have a double bond content of fewer than 3 per molecule.
A double bond content of 1.5 to 2.5 per molecule is preferred.
[0012] The person skilled in the art is aware of such binders and is able to produce them
in accordance with conventional methods to achieve the desired functionality.
[0013] The free-radically polymerizable binders may, for example, comprise prepolymers,
such as, polymers or oligomers, which comprise free-radically polymerizable olefinic
double bonds in the molecule. The polymerizable double bonds may, for example, be
present in the form of (meth)acryloyl, vinyl, allyl, maleate and/or fumarate groups.
The free-radically polymerizable double bonds are particularly preferably present
in the form of (meth)acryloyl groups.
[0014] Examples of prepolymers or oligomers are (meth)acrylic-functional (meth)acrylic copolymers,
epoxy resin (meth)acrylates, polyester (meth)acrylates, polyether (meth)acrylates,
polyurethane (meth)acrylates, amino (meth)acrylates, silicone (meth)acrylates, melamine
(meth)acrylates, unsaturated polyurethanes or unsaturated polyesters. The number average
molecular mass (Mn) of these compounds is preferably from 200 to 8000. (Cyclo)aliphatic
polyurethane (meth)acrylates, polyester (meth)acrylates, (meth)acrylic-functional
poly(meth)acrylates and epoxy (meth)acrylates are preferred. The binders may be used
individually or as a mixture:
[0015] Both here and below, (meth)acrylate, (meth)acrylic and (meth)acryloyl are intended
to mean methacrylate and/or acrylate, methacrylic and/or acrylic, and acryloyl and/or
methacryloyl.
[0016] The filler coating compositions contain component B). Component B) acts as reactive
diluent. Reactive diluents are reactive, polymerizable liquid monomers that act as
solvents for the system and participate in the crosslinking reaction. Components B)
are esters of (meth)acrylic acid with cycloaliphatic alcohols. The alcohols in particular
comprise cycloaliphatic, monohydric branched or unbranched alcohols having 1-20 carbon
atoms per molecule. Cycloaliphatic (meth)acrylates may also optionally be substituted.
The substituents comprise, for example, one or more, for example up to three alkyl
groups, in particular those having 1-4 carbon atoms. Examples of (meth)acrylic acid
esters with cycloaliphatic alcohols are cyclohexyl acrylate, trimethylcyclohexyl acrylate,
4-tert.-butylcyclohexyl acrylate, isobornyl acrylate and the corresponding methacrylates.
(Meth)acrylic acid esters with cycloaliphatic alcohols, such as, isobornyl (meth)acrylate,
cyclohexyl (meth)acrylate and derivatives thereof are particularly preferred as component
B).
[0017] The filler coating compositions contain compounds having at least one phosphoric
acid group as component C). The compounds may comprise low molecular weight and/or
relatively high molecular weight compounds, such as, monomers, oligomers and/or polymers.
The compounds may, for example, have acid values of 200-400 mg of KOH/g, preferably
of 250-350 mg of KOH/g. Component C) compounds preferably contain at least one free-radically
polymerizable double bond. Examples of usable low molecular weight compounds are phosphoric
acid partial esters or phosphoric acid ester derivatives. Examples of usable low molecular
weight compounds comprising olefinic double bonds are modified phosphoric acid partial
esters or phosphoric acid ester derivatives with a molecular mass of, for example,
180 to 500 g/mol. Modification may preferably proceed with (meth)acryloyl groups,
for example, by reaction of phosphoric acid or phosphoric acid derivatives with (meth)acryloyl-functional
monomers, such as, hydroxyalkyl (meth)acrylates having, for example, 1-10, preferably
1-4 C atoms in the alkyl residue. The low molecular weight compounds may be present
as monomers and/or oligomers, for example dimers. Such compounds are also commercially
available, for example under the names "Additol" VXL 6219 (Solutia), ITC 835 (Albright
and Wilson) and Additive 97-070 (Rahn).
[0018] Examples of relatively high molecular weight compounds usable as component C) are
resins modified with phosphoric acid groups and having a number average molecular
mass (Mn) of, for example, 500 to 8000 g/mol. In the preferred case of modification
of component C) with free-radically polymerizable double bonds, the stated resins
may additionally be (meth)acryloyl-functional: The (meth)acryloyl-functional resins
with phosphoric acid groups comprise conventional polyester, polyurethane, polyether,
epoxy and acrylic (meth)acrylates known to the person skilled in the art, which are
appropriately modified, for example by reaction of appropriate epoxy-functional resins
with phosphoric acid or phosphoric acid partial esters.
[0019] In addition to component C), further reactive diluents other than component C) may
also be present. The additional reactive diluents may be used in quantities of, for
example, 1-20 wt.%, relative to the total weight of prepolymers, oligomers and reactive
diluents. The additional reactive diluents may be di- or polyunsaturated, but they
may also comprise monofunctional reactive diluents other than component C). Examples
of monounsaturated reactive diluents are: maleic acid, fumaric acid and the semi-esters
thereof, vinyl acetate, vinyl ethers, substituted vinylureas, styrene, vinyltoluene.
Examples of diunsaturated reactive diluents are: di(meth)acrylates, such as, alkylene
glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate,
vinyl (meth)acrylate, allyl (meth)acrylate, divinylbenzene, dipropylene glycol di(meth)acrylate,
hexanediol di(meth)acrylate. Examples of polyunsaturated reactive diluents are: glycerol
tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate,
pentaerythritol tetra(meth)acrylate. The additional reactive diluents may be used
individually or as a mixture.
[0020] The filler coating compositions that cure under the action of radiation contain photoinitiators.
Suitable photoinitiators include, for example, those which absorb in the wavelength
range from 190 to 600 nm.
[0021] Examples of usable photoinitiators are benzoin and derivatives, acetophenone and
derivatives, such as, 2,2-diacetoxyacetophenone, benzophenone and derivatives, thioxanthone
and derivatives, anthraquinone, 1-benzoylcyclohexanol, organophosphorus compounds,
such as, acyl phosphine oxides. The photoinitiators are used, for example, in quantities
of 0.1-7 wt.%, preferably of 0.5-5 wt.%, relative to the total of free-radically polymerizable
prepolymers, reactive diluents and photoinitiators. The photoinitiators may be used
individually or in combination.
[0022] The filler coating compositions curable by means of high energy radiation may also
contain, in addition to the free-radically polymerizable components free-radically
polymerizable by means of high energy radiation, further components, for example binders
and/or reactive diluents that are chemically crosslinkable by an additional curing
mechanism. Chemically crosslinking binders that may be used are, for example, any
desired two-component binder systems based on a hydroxy-functional component and an
isocyanate-functional component, a hydroxy-functional component and an anhydride component,
a polyamine component and an epoxide component. The additional functional groups and
the double bonds may here be present in the same binder and/or in separate binders.
[0023] The filler coating compositions usable in the process according to the invention
may contain fillers and pigments. These comprise the conventional fillers and organic
or inorganic colored and/or corrosion protection pigments usable in the coatings industry.
Examples of pigments are titanium dioxide, micronized titanium dioxide, iron oxide
pigments, carbon black, azo pigments, zinc phosphate.. Examples of fillers are silicon
dioxide, aluminium silicate, barium sulfate and talcum.
[0024] The filler coating compositions usable in the process according to the invention
may comprise water-based or solvent-based coating compositions. They may contain water
and/or organic solvents. In the case of water-based coating compositions, the binders
present may be ionically or nonionically stabilized in order to achieve sufficient
water dilutability. Alternatively or in addition, it is possible to achieve water
dilutability by means of external emulsifiers. The coating compositions may, however,
also take the form of 100% systems without organic solvents and water.
[0025] The solvents comprise conventional coating solvents. These may originate from the
preparation of the binders or may be added separately. Examples of such solvents are
mono- or polyhydric alcohols, for example, propanol, butanol, hexanol; glycol ethers
or esters, for example, ethylene glycol monobutyl ether, diethylene glycol monobutyl
ether, diethylene glycol dialkyl ethers, dipropylene glycol dialkyl ethers, ethylene
glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene
glycol monobutyl ether acetate, esters, such as, butyl acetate, isobutyl acetate,
butyl acetate, glycols, for example, ethylene glycol, propylene glycol and the oligomers
thereof, N-methylpyrrolidone and ketones, for example, methyl ethyl ketone, acetone,
cyclohexanone; aromatic or linear or branched aliphatic hydrocarbons, for example,
toluene or xylene.
[0026] The filler coating compositions may furthermore contain additives conventionally
used in connection with coatings. Examples of additives conventionally used in connection
with coatings are levelling agents, rheological agents, such as, highly disperse silica
or polymeric urea compounds, thickeners, for example, based on crosslinked carboxy-functional
polymers or on polyurethanes, defoamers, wetting agents, dispersants, anticratering
agents, catalysts. The additives are used in conventional quantities known to the
person skilled in the art.
[0027] The filler coating compositions are produced in the conventional manner known to
the person skilled in the art.
[0028] According to the process according to the invention, the filler layer is first applied
onto a metal substrate.
[0029] The fillers may be applied onto an automotive body or parts thereof as part of a
multilayer coating process.
[0030] The filler layers may particularly advantageously be applied directly onto bright
metal substrates, such as, iron, steel, galvanized steel, aluminium and zinc. Application
may be performed using known methods, preferably by means of spraying.
[0031] Once the filler coating composition has been applied onto one of the above-stated
substrates, the filler layer is exposed, optionally after a flash-off phase to high
energy radiation, preferably UV radiation. Usable UV radiation sources are those emitting
in the wavelength range from 180 to 420 nm, in particular, from 200 to 400 nm. Examples
of such UV radiation sources are optionally doped high, medium and low pressure mercury
vapour emitters, gas discharge tubes, such as, low pressure xenon lamps, unpulsed
UV lasers, UV point source emitters, such as, UV emitting diodes and black light tubes.
[0032] In addition to these continuously operating UV radiation sources, it is, however,
also possible to use discontinuous UV radiation sources, for example pulsed UV lasers
or "high energy flash installations" (known in short as UV flash lamps). The UV flash
lamps may contain a plurality of flash tubes, for example, quartz tubes filled with
inert gas such as, xenon. The UV flash lamps have an illuminance of, for example,
at least 10 megalux and preferably from 10 to 80 megalux per flash discharge. The
energy per flash discharge may be, for example, 1 to 10 kJoule.
[0033] The irradiation time with UV radiation when UV flash lamps are used as the UV radiation
source may be, for example, in the range from 1 millisecond to 400 seconds, preferably,
from 4 to 160 seconds, depending on the number of flash discharges selected. The flashes
may be triggered, for example, about every 4 seconds. Curing may take place, for example,
by means of 1 to 40 successive flash discharges. If continuous UV radiation sources
are used, the irradiation time may be, for example, in the range from a few seconds
to about 5 minutes, preferably, less than 5 minutes.
[0034] The distance between the UV radiation sources and the substrate surface to be irradiated
may be, for example, 5 to 60 cm.
[0035] If required, once the filler layer has been applied and irradiated, one or more further
similar filler layers may be applied in further operations and exposed to UV irradiation.
[0036] If the filler coating compositions contain binders which cure by an additional crosslinking
mechanism, the coatings may be left after the irradiation operation to cure completely
at room temperature, for example, for 16 to 24 hours. It is also possible to perform
complete curing at higher temperatures of, for example, 30 to 130°C, preferably of
40 to 80°C. Complete curing may take place by conventional methods, for example, in
a heated booth or by means of IR radiation. Depending upon the curing temperature,
curing times of for example 1 to 60 minutes are possible. Thermal curing may, of course,
also be performed before the irradiation phase or before and after the irradiation
phase.
[0037] The filler coating compositions usable in the process according to the invention
may be used as a sandable filler and particularly advantageously, as a priming filler.
[0038] Once the filler layer has been cured by means of high energy radiation, in accordance
with the process according to the invention the filler layer is overcoated with a
top coat of a colored and/or special effect base coat layer and a transparent clear
coat layer or a top coat of a pigmented one-layer top coat. No particular restrictions
apply with regard to the base, clear and one-layer top coat coatings that are to be
used at this point.
[0039] Any solvent- or water-based base coatings known to the person skilled in the art
and conventional in automotive coating, in particular in repair coating, are suitable
as the colored and/or special effect coatings for the base coat/clear coat top coat.
Examples of solvent-based base coatings are those based on polyacrylate and/or polyester
resins, optionally, in combination with melamine resins and cellulose esters. Examples
of water-based coatings are those based on physically drying polyurethane, polyurethane/urea,
polyester, polyesterurethane and/or polyacrylate resins and the modifications thereof,
such as, acrylated or silicon-modified polyurethane and/or polyester resins. Further,
water-based coatings that may be considered are those prepared from chemically crosslinking
binder components, for example, from binders containing hydroxyl groups and polyisocyanate
crosslinking agents. Curing of the base coat may proceed at room temperature or be
forced at, for example, 40-80°C or at higher temperatures up to, for example, 130°C.
The base coat layer, however, optionally after a flash-off phase, also may be overcoated
wet-on-wet with a clear coat and then be cured together with the clear coat at the
above-stated temperatures.
[0040] Any solvent- or water-based clear coatings known to the person skilled in the art
and conventional in automotive coating, in particular in repair coating, are suitable
as the clear coatings for the base coat/clear coat top coat. Examples of such coatings
are solvent-based or aqueous clear coatings based on binders containing hydroxyl groups
and/or amino groups and polyisocyanate crosslinking agents and those based on binders
containing amino groups and acryloyl groups. Curing of the clear coat layer may proceed
at room temperature or be forced at, for example, 40-80°C or at higher temperatures
up to, for example, 130°C.
[0041] Alternatively, the top coat applied onto the filler layer may also comprise a pigmented
one-layer top coat of a conventional solvent- or water-based pigmented one-layer top
coat coating composition, which is cured at the above-stated temperatures.
[0042] As base coat, clear coat and/or one-layer top coat for preparing the top coat layer
are also suitable coating compositions curable by means of UV radiation.
[0043] The process according to the invention may be used in automotive and industrial coatings,
particularly advantageously in repair coatings, in particular in repair coatings of
vehicles and vehicle parts.
[0044] By means of the process according to the invention, filler layers are obtained that
have excellent adhesion onto various metal substrates, such as, iron, steel, galvanized
steel, aluminium and zinc. The filler coating compositions applied in the process
according to the invention have good processing properties and exhibit a good balance
between good stability and satisfactory flow. When repair coating areas that have
been sanded back to the substrate, no edge marks occur when the filler layers are
overcoated with a top coat.
[0045] The following Examples are intended to illustrate the invention in greater detail.
[0046] All values are stated by weight.
pbw = parts by weight.
Examples
Example 1
Production of a urethane acrylate (component A)
[0047] A mixture of 521 pbw of hexamethylene diisocyanate isocyanurate and 0.9 pbw of methylhydroquinone
was initially introduced in a 2 litre glass reactor equipped with a temperature sensor,
stirrer and dropping funnel and heated to 60°C. A mixture of 211 pbw of hydroxyethyl
acrylate, 67 pbw of n-butanol and 0.1 pbw of dibutyltin dilaurate was added dropwise
to said first mixture in such a manner that the temperature did not rise above 80°C.
The reaction mixture was then kept at 80°C until the NCO value was below 0.1%. The
mixture was then diluted with 200 pbw of isobornyl acrylate. A colorless, viscous
resin with an acryloyl functionality of 2, a solids content (1h/150°C) of 79.7% and
a viscosity (25°C) of 22700 mPas was obtained.
Example 2
Production of a filler coating composition
[0048] A filler coating composition was produced from the following components:
23 pbw of urethane acrylate according to Example 1
50 pbw of isobornyl acrylate
1 pbw of"Disperbyk"110 (dispersion additive; 53% solution of a copolymer with acidic
groups; Byk)
0.01 pbw of carbon black
1.0 pbw of titanium dioxide
0.5 pbw of Aerosil® (silica)
8.0 pbw of kaolin
4.0 pbw of talcum
13.0 pbw of barytes
2 pbw of "Irgacure" 819 (phosphine oxide based photoinitiator; CIBA)
4 pbw of "Additol" VXL 6219 (acrylic-modified phosphoric acid ester, acid value 320
mg KOH/g; Solutia)
Example 3
Production of a multilayer structure
[0049] A filler layer of the filler coating composition produced in Example 2 was applied
by spraying onto bright sheet steel to yield a dry layer thickness of 150 µm. Immediately
after application, the filler layer was exposed to irradiation by the UV flash lamp
(3500 Ws). Irradiation was performed by 30 flashes; a flash being triggered every
4 seconds.
[0050] A damaged OEM coating on sheet steel was also repaired, the damaged area being sanded
and cleaned for this purpose. The coating was sanded right back to the sheet steel.
A filler layer was sprayed onto the sanded damaged area to yield a dry layer thickness
of approx. 150 µm. Immediately after application, irradiation was performed with a
UV flash lamp as described above.
[0051] The filler layers were then each overcoated with a conventional commercial solvent-based,
yellow-pigmented two-component top coat based on hydroxyacrylate/polyisocyanate ("Standocryl
2K-Autolack"; Standox GmbH). Curing was performed for 30 minutes at 60°C.
Presentation of coating results
Adhesion to substrate
[0052] The steel sheet previously coated with filler and top coat was subjected, after 3
days' storage at room temperature, to a condensing water constant climate test (to
DIN 50017) for 72 hours. After 24 hours regeneration at room temperature, crosshatching
(to DIN 53151), degree of blistering (to DIN 53209) and gloss (to DIN 67530) were
evaluated.
Crosshatching result: 0-1
Blistering result: m0/ g0
Gloss measurement result: 20° = 85 units/60° = 93 units
[0053] The crosshatching and degree of blistering evaluations revealed very good adhesion
results.
[0054] The filler layer exhibited elevated solvent resistance, as a result of which the
gloss values of the subsequently applied top coat are excellent.
[0055] The repaired OEM coating that had been sanded back to the substrate exhibited no
internal or external edge marks.
[0056] The filler coating compositions were straightforward to process and could be applied
using conventional filler spray guns.
[0057] Flow of the filler coating composition was very good, as was stability. Layer thicknesses
of 150 µm could be applied in a single spray pass without an intermediate flash-off
time.
1. A process for multilayer coating of substrates which comprises
a) applying a filler layer of a filler coating composition to a metal substrate,
b) curing the resultant filler layer by irradiation with high energy radiation and
c) applying a top coat layer to the cured filler layer and curing the top coat layer,
whereby the filler coating composition comprises
A) at least one binder capable of free-radical polymerization having fewer than three
olefinic double bonds per molecule,
B) at least one ester of alpha,beta-olefinically unsaturated monocarboxylic acids
capable of free-radical polymerization having one olefinic double bond per molecule,
wherein the at least one ester of alpha,beta-olefinically unsaturated monocarboxylic
acids is a (meth)acrylic acid ester with cycloaliphatic alcohols,
and
C) at least one compound having at least one phosphoric acid group.
2. The process according to claim 1, wherein the top coat layer comprises a colored and/or
special effect base coat coating composition and a transparent clear coat coating
composition applied over the base coat coating composition.
3. The process according to claim 1, wherein the top coat layer comprises a pigmented
one-layer top coat coating composition.
4. The process according to one of claims 1 to 3, wherein the filler coating composition
comprises 10-80 weight-% of component A) and 20-90 wt.% of component B) and wherein
the weight percentages of component A) and B) add up to 100 wt.%.
5. The process according to one of the preceding claims, wherein the filler coating composition
comprises 1-15 weight-% of component C), relative to the total quantity of the filler
coating composition.
6. The process according to one of the preceding claims, wherein the filler coating composition
comprises as component A) at least one binder capable of free-radical polymerization
having 1.5 to 2.5 olefinic double bonds per molecule.
7. The process according to claim 6, wherein the filler coating composition comprises
as component B) isobomyl (meth)acrylate.
8. The process according to one of the preceding claims, wherein the filler coating composition
comprises as component C) at least one compound having at least one phosphoric acid
group and at least one free-radically olefinic double bond.
9. The process according to claim 8, wherein the filler coating composition comprises
as component C) at least one (meth)acryloyl-modified phosphoric acid derivative.
10. The process according to one of the preceding claims, wherein it is a process for
repair coating of substrates.
11. The process according to one of the preceding claims, wherein it is a process for
applying automotive, automotive part and /or industrial coatings.
1. Verfahren zur Mehrlagenbeschichtung von Substraten, welches die folgenden Schritte
umfasst:
a) Auftragen einer Fülllage einer Beschichtungszusammensetzung eines Füllmittels auf
ein Metallsubstrat,
b) Härten der resultierenden Fülllage durch eine Bestrahlung mit einer Hochenergiestrahlung
und
c) Auftragen einer Deckbeschichtungslage auf die gehärtete Fülllage und ein Härten
der Deckbeschichtungslage,
wobei die Beschichtungszusammensetzung des Füllmittels enthält;
A) mindestens ein Bindemittel, das in der Lage ist, eine Polymerisation durch freie
Radikale einzugehen und das weniger als drei olefinische Doppelbindungen pro Molekül
aufweist,
B) mindestens einen Ester von alpha,beta-olefinisch ungesättigten Monocarboxylsäuren,
welcher in der Lage ist, eine Polymerisation durch freie Radikale einzugehen und welcher
eine olefinische Doppelbindung pro Molekül aufweist, wobei der mindestens eine Ester
von alpha,beta-olefinisch ungesättigten Monocarboxylsäuren ein (meth)acrylsäureester
mit cycloaliphatischen Alkoholen ist, und
C) mindestens eine Verbindung, die mindestens eine Phosphorsäuregruppe aufweist.
2. Verfahren gemäß Anspruch 1, bei dem die Deckbeschichtungslage eine farbige und/oder
einen Spezialeffekt hervorrufende Beschichtungszusammensetzung für den Grundüberzug
und eine durchsichtige Beschichtungszusammensetzung für einen Klarüberzug enthält,
welcher über die Beschichtungszusammensetzung für den Grundüberzug aufgetragen wird.
3. Verfahren gemäß Anspruch 1, bei dem die Deckbeschichtungslage aus einer pigmentierten,
einlagigen Beschichtungszusammensetzung für den Decküberzug besteht.
4. Verfahren gemäß den Ansprüchen 1 bis 3, bei dem die Füllmittelbeschichtungszusammensetzung
10 bis 80 Gewichtsprozent einer Komponente A) und 20 bis 90 Gewichtsprozent einer
Komponente B) enthält und wobei die Gewichtsprozente der Komponente A) und der Komponente
B) sich zusammen auf 100 Gewichtsprozent aufsummieren.
5. Verfahren gemäß einem der vorhergehenden Ansprüche, bei dem die Füllmittelbeschichtungszusammensetzung
1 bis 15 Gewichtsprozent einer Komponente C) enthält, bezogen auf die gesamte Menge
der Füllmittelbeschichtungszusammensetzung.
6. Verfahren gemäß einem der vorhergehenden Ansprüche, bei dem die Füllmittelbeschichtungszusammensetzung
als die Komponente A) mindestens ein Bindemittel enthält, das in der Lage ist, eine
Polymerisation durch freie Radikale einzugehen, und das 1,5 bis 2,5 olefinische Doppelbindungen
pro Molekül aufweist.
7. Verfahren gemäß Anspruch 6, bei dem die Füllmittelbeschichtungszusammensetzung als
die Komponente B) Isobornyl(meth)acrylat enthält.
8. Verfahren gemäß einem der vorhergehenden Ansprüche, bei dem die Füllmittelbeschichtungszusammensetzung
als die Komponente C) mindestens eine Verbindung enthält, welche mindestens eine Phosphorsäuregruppe
und mindestens eine olefinische Doppelbindung mit freien Radikalen aufweist.
9. Verfahren gemäß Anspruch 8, bei dem die Füllmittelbeschichtungszusammensetzung als
die Komponente C) mindestens ein (meth)acryloyl-modifiziertes Phosphorsäurederivativ
aufweist.
10. Verfahren gemäß einem der vorhergehenden Ansprüche, bei dem dasselbe ein Verfahren
zur Reparatur von Beschichtungen auf Substraten darstellt.
11. Verfahren gemäß einem der vorhergehenden Ansprüche, bei dem dasselbe ein Verfahren
zum Auftragen von Automobil-, Automobilteilen- und/oder industriellen Beschichtungen
darstellt.
1. Procédé pour le revêtement multicouche de substrats qui comprend:
a) l'application d'une couche de remplissage d'une composition de revêtement de remplissage
sur un substrat métallique,
b) le durcissement de la couche de remplissage résultante par une irradiation avec
un rayonnement à haute énergie, et
c) l'application d'une couche de revêtement de finition sur la couche de remplissage
durcie et le durcissement de la couche de revêtement de finition,
en conséquence de quoi la composition de revêtement de remplissage comprend:
A) au moins un liant apte à une polymérisation par radicaux libres possédant moins
de trois liaisons doubles oléfiniques par molécule,
B) au moins un ester d'acides monocarboxyliques α,β-oléfiniquement insaturés apte
à une polymérisation par radicaux libres possédant une liaison double oléfinique par
molécule, le au moins un ester d'acides monocarboxyliques α,β-oléfiniquement insaturés
étant un ester d'acide (méth)acrylique avec des alcools cycloaliphatiques, et
C) au moins un composé possédant au moins un groupe d'acide phosphorique.
2. Procédé suivant la revendication 1, dans lequel la couche de revêtement de finition
comprend une composition de revêtement de couche de base colorée et/ou à effet spécial
et une composition de revêtement de couche claire transparente appliquée sur la composition
de revêtement de couche de base.
3. Procédé suivant la revendication 1, dans lequel la couche de revêtement de finition
comprend une composition de revêtement de couche de finition monocouche pigmentée.
4. Procédé suivant l'une quelconque des revendications 1 à 3, dans lequel la composition
de revêtement de remplissage comprend 10 à 80% en poids de composant A) et 20 à 90%
en poids de composant B) et dans lequel les pourcentages en poids des composants A)
et B) s'élèvent à 100% en poids.
5. Procédé suivant l'une quelconque des revendications précédentes, dans lequel la composition
de revêtement de remplissage comprend 1 à 15% en poids de composant C), relativement
à la quantité totale de la composition de revêtement de remplissage.
6. Procédé suivant l'une quelconque des revendications précédentes, dans lequel la composition
de revêtement de remplissage comprend comme composant A) au moins un liant apte à
une polymérisation par radicaux libres possédant de 1,5 à 2,5 liaisons doubles oléfiniques
par molécule.
7. Procédé suivant la revendication 6, dans lequel la composition de revêtement de remplissage
comprend comme composant B) le (méth)acrylate d'isobornyle.
8. Procédé suivant l'une quelconque des revendications précédentes, dans lequel la composition
de revêtement de remplissage comprend comme composant C) au moins un composé possédant
au moins un groupe d'acide phosphorique et au moins une liaison double oléfinique
polymérisable par radicaux libres.
9. Procédé suivant la revendication 8, dans lequel la composition de revêtement de remplissage
comprend comme composant C) au moins un dérivé d'acide phosphorique modifié par un
(méth)acryloyle.
10. Procédé suivant l'une quelconque des revendications précédentes, qui est un procédé
pour réparer un revêtement de substrats.
11. Procédé suivant l'une quelconque des revendications précédentes, qui est un procédé
pour appliquer des revêtements automobiles, de pièces automobiles et/ou industriels.